Today, computer systems typically use some sort of cursor displayed on a screen to enable the user to select commands or perform other input functions. Currently, cursor control is accomplished through relative motion devices, such as mouses, or direct contact of the display, such as with a touch screen. Relative motion devices control cursor motion. However, the movement of the cursor is not equal to the movement of the relative motion device. A direct control device allows inputs to be made by physically touching a location of the screen. Both of these types of cursor control have a physical interface to a computer. However, these relative motion devices are too limiting. Therefore, it would be desirable to provide a cursor control device having no physical interface to the system.
In the course of business, these presentations are often performed for a variety of purposes. Often, presentations are performed by individuals using overhead projections of images, graphs, charts, etc. Recently, more sophisticated businesses and scientific presentations have included interactive multi-media and color. Software, such as Microsoft PowerPoint.TM., for example, and hardware are becoming more common for such presentations. In fact, currently, portable laptop computers may be connected to digital display screens on overhead projectors.
One problem with the interactive and multi-media presentation is the hardware may be bulky, which may hinder an individual or limit that amount of material that an individual may bring to a presentation. It is desirable to reduce the amount of hardware necessary to support such presentations.
One goal of a presentation is to provide accurate, up-to-date information. Sources of this type of information include networks and distributed databases, such as digital libraries, data jukeboxes, servers and the World Wide Web (the Web).
Currently, the largest computer network in existence is the Internet. The Internet is a worldwide interconnection of computer networks that communicate using a common protocol. Millions of computers, from low end personal computers to high-end super computers are coupled to the Internet.
In 1989, a new type of information system known as the World Wide Web (the Web) was introduced to the Internet. Early development of the Web took place at CERN, the European Particle Physics Laboratory. The Web is a wide-area hypermedia information retrieval system that gives wide access to a large universe of documents. Initially, the Web was only known to and used by the academic/research community because there was no easily available tool which allows a technically untrained person to access the Web.
In 1993, the National Center for Supercomputing Applications (NSCA) released a Web browser called "Mosiac" that implemented a graphical user interface (GUI). Mosiac's GUI was simple to learn yet powerful and allowed users to retrieve documents from the Web using simple point-and-click commands. Because the user does not have to be technically trained and the browser is easy to use, Web browsers have the potential of opening the Internet to the masses.
The architecture of the Web follows a conventional client-server model. The terms "client" and "server" are used to refer to a computer's general role as a requester of data (the client) or provider of data (the server). In the Web environment, Web browsers reside in clients and Web documents reside in servers. Web clients and Web servers communicate using a protocol called "HyperText Transfer Protocol" (HTTP). A browser, such as Mosaic opens a connection to a server and initiates a request for a document. The server delivers the requested document, typically in the form of a text document coded in a standard HyperText Markup Language (HTML) format.
Portions of documents displayed on the Web typically contain hypertext links that link graphics or text in one document with another document on the Web. Documents containing hypertext links are created prior to their "publishing" on the Web. That is, a document that is to be published is provided to a server which creates the document and, essentially, publishes the document by permitting its access by others on the Web. Each hypertext link is associated with a Universal Resource Locator (URL) that identifies and locates a document on the Web. When a user selects a hypertext link, using, for instance, a cursor, the graphical browser retrieves the corresponding document(s) using a URL(s).
The present invention provides for a pointing device that controls the cursor on a display based on the absolute positioning of the cursor control device with respect to the screen. The pointing device of the present invention may be used to access and display documents such as those retrieved from the Web and which may be part of the presentation.
As the trend towards high quality, multi-media productions continues to grow, people may desire to have access to networks, including uses of such academic documents for use in the presentations. The present invention provides such access. As will be described below, the present invention provides an apparatus for making presentations of on-line documents.